Chapter 35: Hypothalamus Flashcards
(89 cards)
As its name implies, the hypothalamus is _____ to the thalamus. The hypothalamus is also anterior to the thalamus.
- Inferior
Like the thalamus, the hypothalamus is split into right and left halves by the _____ ventricle.
- Third
The most anterior part of the hypothalamus is the lamina terminalis which forms the _____ wall of the _____ ventricle.
- Anterior
- Third
Since the lamina terminalis is above and slightly anterior to the optic chiasma, the nuclei in the lamina terminalis are called the _____ nuclei.
- Pre-optic
The medial and lateral preoptic nuclei are the most _____ nuclei of the _____.
- Anterior
- Hypothalamus
The hypothalamus regulates the viscera. Thus, the highest centers of the autonomic nervous system are in the _____.
- Hypothalamus
The medial preoptic nucleus is an _____ nucleus regulating the body’s cooling mechanisms.
- Autonomic
The medial preoptic nucleus causes cutaneous vasodilation by way of a polysynaptic pathway. Cutaneous vasodilation _____ the body.
- Cools
The _____ nucleus also initiates sweating to further _____ the body.
- Medial preoptic
- Cool
Since it contains more than 2 neurons, the control of sweating is also a _____ pathway.
- Polysynaptic
When body temperature exceeds the setpoint of 37 degrees C, dopaminergic nerves activate the _____ nucleus by releasing _____ on its D1 receptors.
- Medial preoptic
- Dopamine
Release of dopamine onto _____ receptors on neurons of the medial preoptic nucleus initiates _____ mechanisms such as _____ and _____.
- D1
- Cooling
- Vasodilation
- Sweating
Blocking the D1 receptors in the medial preoptic nucleus causes a _____ in body temperature.
- Rise
In hypersensitive patients, blocking _____ receptors can cause a high fever.
- D1
Fever may also be caused by cytokines, such as prostaglandin E2, that _____ the response of neurons in the _____ nucleus to dopamine.
- Inhibit
- Medial preoptic
The interstitial nuclei of the hypothalamus are embedded in the medial preoptic nucleus. The nucleus designated INAH3 is the _____ interstitial nucleus of the anterior _____ as one counts from superior to inferior.
- Third
- Hypothalamus
The third interstitial nucleus of the anterior hypothalamus has different inputs and larger neurons in heterosexual men than in homosexual men. We thus assume that sexual orientation is determined by the _____ nucleus of the _____ and its connections.
- Third interstitial
- Anterior hypothalamus
The female pheromone estratetraeneone stimulates the _____ nucleus of the _____ hypothalamus in heterosexual men but not in homosexual men.
- Third interstitial
- Anterior
The optic chiasma is below and just behind the lamina terminalis. The supraoptic region of the hypothalamus is _____ optic chiasma and just behind the _____ nuclei in the lamina terminalis.
- Above (superior)
- Preoptic
The suprachiasmatic nucleus is the most inferior nucleus of the supraoptic region. It lies on the superior surface of the _____ and receives a small input from it.
- Optic chiasma
The suprachiasmatic nucleus receives input from the intrinsically photreceptive ganglion cells of the retina via the _____ and uses this input to regulate one’s circadian rhythm.
- Optic chiasma
Melatonin secreted by the _____ gland reaches the suprachiasmatic nucleus through the _____ and contributes to setting the _____ rhythm.
- Pineal
- Blood
- Circadian
Circadian rhythm is synchronized with daylight by the input of the _____ of the retina and to the _____ nucleus.
- Intrinsically photosensitive ganglion cells
- Suprachiasmatic
The anterior nucleus of the hypothalamus sits above the suprachiasmatic nucleus in the medial part of the _____ region. Despite its name, the “anterior nucleus” of the hypothalamus must be posterior to the _____ nucleus of the hypothalamus.
- Supraoptic
- Medial preoptic